Reply by Nicky

That’s a lot of wood!

First, be sure the wood’s moisture content is suitable for your area. If you live where relative humidity is high, 10%-12% may be acceptable. I live is a high desert environment, I shoot for 6%-8%. Rough cut and plane is OK when you get it, but leave a little for your final dimensions, after it’s been acclimated to your shop. Once wood is properly dried it will expand and contract with changes in humidity, but not twist if you’ve machine it flat and square.

For your application, you need straight grain lumber. Although wild walnut patterns can be a nice design element, I believe that it would contribute to the twist you’re trying to avoid.

-- Nicky